The option “DATATYPE” controls the datatype which is used during creation of the RRD database. Default is “GAUGE”. For consecutive values the type should be “COUNTER”. Plugin-developers should use the unit “c” for counters but this is not always the case.

To set all datasources to COUNTER

DATATYPE = COUNTER

Setting datasources to different types

DATATYPE = GAUGE,GAUGE,COUNTER,COUNTER

This option has effect only during creation of the RRD database.

More datatypes are explained in the RRDTool documentation found at rrdcreate.